frontend: Adjust missing files dialog

[Warchamp7]

Description

The primary commit in this PR adds support for recursive searching for missing files.

Whenever a missing file is successfully located, the search will also expand to 2 subfolders deep from the matched location. If a file is found within a subfolder, it will again search up to 2 subfolders deep from that location.

Note

The existing file check behaviour looks in the specified directory for files that match the missing filename. This currently does not have any protection against a scenario where a scene collection might contain files that share the same filename but are inside different folders. I'm open to discussion on whether we feel this is necessary.

This also does some additional cleanup:

• Ellides the filepath to the new file in the middle
• Only stretches the new filepath column
• Adjusts the default window size
• Enforces a minimum window size
• Fixes a bug when locating only a single file that caused the additional files prompt to appear twice

Motivation and Context

It is currently very tedious selecting every new directory that the files are now located in individually. In many cases, a number of resources may be located within the same parent folder but are organized into subfolders.

How Has This Been Tested?

Relocated the files for a scene collection with a large number of folders to a new directory. Selected the parent folder of all the resources and all files were located in one search.

Types of changes

• Bug fix (non-breaking change which fixes an issue)

• Tweak (non-breaking change to improve existing functionality)

Checklist:

• My code has been run through clang-format.
• I have read the contributing document.
• My code is not on the master branch.
• The code has been tested.
• All commit messages are properly formatted and commits squashed where appropriate.
• I have included updates to all appropriate documentation.